In human anatomy, the axillary vein is a large blood vessel that conveys blood from the lateral aspect of the thorax, axilla (armpit) and upper limb toward the heart. There is one axillary vein on each side of the body. Its origin is at the lower margin of the teres major muscle and a continuation of the brachial vein. It is accompanied along its course by a similarly named artery, the axillary artery.